河北省主要苹果产区土壤养分状况与演变

通过对河北省主要果园产区的土壤养分测定、定位监测等方法,研究了河北省土壤养分现状与动态变化及其养分在0~60 cm土壤剖面的分布特点,旨在为苹果的科学施肥提供理论依据。主要结果:河北省主要苹果园0~20 cm土壤全氮、有机质、有效磷、速效钾、有效铁、有效锌平均含量分别为1.16 g/kg、17.99 g/kg、118.26 mg/kg、329.70 mg/kg,15.33 mg/kg、3.69 mg/kg,同比于第二次土壤普查时期,各养分含量分别增加了0.43 g/kg、6.49 g/kg、111.96 mg/kg、201.50 mg/kg、7.13 mg/kg、3.16 mg/kg。有机质及养分含量分布:基于第二次土壤普查分级标准,土壤有机质在10.00~20.00 g/kg的果园占60.3%,处于较低水平;全氮在1.00~1.50 g/kg果园占44.5%,处于中等水平;有效磷>40.00 mg/kg、速效钾>200.00 mg/kg分别占78.5%、61.8%,均处于较高水平。随着果园种植时间的增加,果园土壤养分含量均呈直线增加趋势,有效磷和速效钾积累速率显著高于全氮、有机质、有效铁、有效锌的增加速率。土壤养分空间分布特点:土壤养分以0~20 cm积累为主,定位实验31年的果园中20~40和40~60 cm土层土壤有机质、有效磷、速效钾分别相当于0~20 cm的50.8%、59.8%、74.0%和42.3%、27.0%、55.9%。在种植年限为30~40年的果园中,土壤pH明显降低,其0~20、20~40、40~60 cm土层土壤pH值较小于10年果园分别下降1.09、0.41、0.27个单位。主要结论:苹果园土壤有效磷、速效钾积累与树龄呈直线相关,且土壤有效磷、速效钾增幅显著高于土壤有机质、有效铁、有效锌的增幅,是导致土壤养分失衡的主要原因;建议增施有机肥、配合适量铁肥和锌肥平衡果园土壤养分以逐渐提高果园土壤供肥生产能力。

Soil nutrient status and evolution of main apple producing areas in Hebei Province

Extensive measurements on soil nutrients over main orchard producing areas in combination with in situ monitoring at some sites were conducted in this study to investigate the current status,dynamic changes as well as the vertical distribution of nutrients in 0~60 cm soil for providing insightful support for the scientific recommendation of nutrient management.Results showed that:the contents of total nitrogen,organic matter,available phosphorus,available potassium,available iron and available zinc in 0~20 cm soil of main apple orchard in Hebei Province were 1.16 g/kg,17.99 g/kg,118.26 mg/kg,329.70 mg/kg,15.33 mg/kg and 3.69 mg/kg,respectively,which were greater of 0.43 g/kg,6.49 g/kg,111.96 mg/kg,201.50 mg/kg,7.13 mg/kg and 3.16 mg/kg,respectively compared with the second soil survey in 1980~1985.Status of soil organic matter and nutrients:based on the standards of the second soil census,orchard with 10.00~20.00 g/kg of soil organic matter accounted for 60.3%,which was at a low level;orchard with 1.00~1.50 g/kg of total nitrogen accounted for 44.5%,which was at a medium level;available phosphorus>40.00 mg/kg and available potassium>200.00 mg/kg accounted for 78.5%and 61.8%respectively,which were all at a high level.Meanwhile,soil nutrients linearly increased with the orchard cultivation,where the increases of soil available phosphorus and potassium were greater than the values of soil total nitrogen,organic matter,available iron and available zinc.Status of vertical distribution of soil nutrients:soil nutrients in the 30-year old orchard mainly accumulated in the 0~20 cm soil,and the available phosphorus and available potassium in the 20~40 and 40~60 cm soil layers were approximately 50.8%,59.8%,74.0%and 42.3%,27.0%and 55.9%of those in 0~20 cm,respectively.Soil pH decreased clearly after 30~40 years cultivation,and it was about 1.09,0.41 and 0.27 lower than the values of 0~20,20~40 and 40~60 cm layers of orchard in 10 years,respectively.In conclusion,soil nutrients of apple orchard linearly increased with cultivation years although the soil available phosphorus and potassium increased much faster than those of soil organic matter,available iron and zinc,indicating a trend of soil nutrients imbalance,degradation and acidification.Therefore,increasing application of organic fertilizers,iron and zinc will be helpful for improving the soil fertility production capacity of apple orchard in Hebei.